“The choice facing the British people on June 23 is increasingly clear: the certainty and economic security of remaining in the EU, or a leap in the dark that would raise prices – including the cost of a family holiday.”

easyJet CEO Carolyn McCall told workers that Britain’s EU membership is integral to the future of the Luton Airport based airline.

Ms McCall said: “If the UK were to vote to leave the EU any new, more restrictive aviation arrangements would add cost and therefore fares are highly likely to rise.

“And a weaker pound would mean the cost of a holiday abroad – including food, accommodation and drinks – would be more expensive.

“That is why we think it is better for our customers to remain in the EU.”

Following his speech Mr Cameron held a question and answer session with staff in Hangar 89.

When asked if he has booked a summer holiday with his wife Samantha, the Prime Minister admitted that he has had some “pretty good ideas” but that he would not tip off the press.